A VALVE AND ACTUATOR IN COMBINATION

摘要

A valve (2) and actuator (3) in combination with a transportation tank (403, 1102) to operate off of low pneumatic pressures including a valve (2) and a valve body (4) with a tank end (5), a valve seat (23, 24) near the tank end (5) of the valve body (4), the valve seat having a value sealing surface (2325); a stem chamber (7) extending through the valve body (4), the stem chamber (7) having an actuator port (22), a seat port (21), and an outlet port (8); a valve stem (13) slidably positioned in the stem chamber (7), the valve stem (13) having a plug end (14) and a plug (17) attached to the plug end (14), the plug (17) having a plug sealing surface (25, 26) to sealingly contact the valve sealing surface (23, 24); an actuator (3) has a hollow housing (100) with a valve end (10), the valve end (10) attached to the valve body (4); a plurality of piston assemblies (103), each having a piston (104) slidable in the housing (100) and a partition (105) fixed in the housing (100), the piston (104) and the partition (105) defining an actuator chamber (107).